Mower won't start, won't click.

I got on YouTube and looked for the no click, no anything ,as I've already replaced the Solenoid last month. Everyone was saying on there that it was probably the keyswitch. I took mine off and took it to the part store and got a new one. I'm a 54-year-old woman that weighs like 115 pounds I don't have a lot of strength in my hands. The instruction said not to force it on. I put it on somewhat but I didn't look at it when I was pulling it off I just found out online where to find it and I don't know if it was pushed all the way in. I cannot get it to go all the way on only about halfway maybe, maybe cover in the pins halfwayso somebody could just tell me if that would keep it from starting?